[Machine] The Prophet ﷺ never took off his shoes in prayer except for once. When he removed them, the people followed his example. He then asked, "Why did you do that?" They replied, "You took off your shoes, so we did too." The Prophet ﷺ said, "Indeed, Gabriel informed me that there was some impurity or harm in them."
أَنَّ النَّبِيَّ ﷺ لَمْ يَخْلَعْ نَعْلَيْهِ فِي الصَّلَاةِ قَطُّ إِلَّا مَرَّةً وَاحِدَةً خَلَعَ فَخَلَعَ النَّاسُ فَقَالَ «مَا لُكُمْ» قَالُوا خَلَعْتَ فَخَلَعْنَا فَقَالَ «إِنَّ جِبْرِيلَ أَخْبَرَنِي أَنَّ فِيهِمَا قَذَرًا أَوْ أَذًى»